Hello, I have a history of Stage IIB Breast Cancer. I am 12 years out, but have been experiencing intermittent pain in my sternum and directly behind the sternum in my spine. It seems to be getting more painful each time it flares up. Should I be concerned? I do work in a lab, and found both calcium and alk phos to be normal the last time. I ve not tested this time, but could if that would be beneficial. The last time was about 4 weeks ago, I believe.